WHAT: HIV is coated in sugars that usually hide the virus from the immune system. Newly published research reveals how one broadly neutralizing HIV antibody actually uses part of the sugary cloak to help bind to the virus. The antibody binding site, called the V1/V2 region, represents a suitable HIV vaccine target, according to the scientists who conducted the study. In addition, their research reveals the detailed structure of the V1/V2 region, the last part of the virus surface to be visualized at the atomic level.

Guppies in the wild have evolved over at least half-a-million years — long enough for the males' coloration to have changed dramatically. Yet a characteristic orange patch on male guppies has remained remarkably stable, though it could have become redder or more yellow. Why has it stayed the same hue of orange over such a long period of time?

A new study has revealed that immature neurons taken from healthy mouse embryos can repair damaged brain circuitry and partially normalize metabolism when transplanted into adult mice that have grown morbidly obese due to a genetic deficiency. This proof-of-principle discovery represents one step down a long road toward neuronal replacement therapy, which researchers hope might one day be used to repair brains that have been injured by trauma or disease.